从肠道菌群参与的胆碱-氧化三甲胺代谢途径探讨清血消脂片抗动脉粥样硬化作用机制

Recently discovered trimethylamine oxide, the metabolites of choline with the involvement of intestinal flora, has the pro-atherosclerotic effect. Our previous studies have confirmed the presence of choline metabolism in hyperlipidemia and the process of atherosclerosis .Qingxue Xiaozhi tablets, which can degradate phlegm and active blood, has an affirmatory effect of regulating lipid metabolism disorders and anti-atherosclerosis, and the previous researches indicated that Qingxue Xiaozhi tablets also had an regulatory effect on the metabolite of choline in the intestinal.The present study will focus on the intestinal flora to analysis the features of intestinal flora in the atherosclerosis model in ApoE deficient mice fed the high-fat diet with the choline and trimethylamine oxide added in, using the metabolomics or the sequencing of 16S rRNA and metagenomic, and to investigate the effect of Qingxue Xiaozhi tablets on the regulation of intestinal flora , choline metabolism disorders and the anti-atherosclerosis effect.Then clarifying the molecular mechanisms of the pro-atherosclerotic effect of trimethylamine oxide and the mechanisms of Qingxue Xiaozhi tablets from the formation of foam cells and the uptake and retrograde transport of cholesterol, providing some new ideas and methods for the prevention of the metabolic diseases correlated with the disorders of intestinal flora and the researches of cardiovascular diseases. Ultimately, revealing the mechanisms of degradate phlegm and active blood to provide scientific evidence for the clinical application of Qingxue Xiaozhi tablets.

胆碱-氧化三甲胺（TMAO）代谢是脂代谢中磷脂代谢的重要途径。新近发现肠道菌群参与的胆碱代谢产物TMAO具有促动脉粥样硬化作用。我们的研究表明清血消脂片具有明确的抗动脉粥样硬化作用，初步研究提示清血消脂片对肠道胆碱代谢物及肠道菌群结构具有调节作用。提出“清血消脂片抗动脉粥样硬化的作用与其改善肠道菌群结构及胆碱-氧化三甲胺代谢紊乱有关，具体机制涉及胆固醇摄取与逆转运”的假说。拟围绕肠道菌群，利用代谢组学方法和16S rRNA 和宏基因组测序技术分析添加胆碱及TMAO的高脂饲料喂饲的ApoE-/- 小鼠动脉粥样硬化模型肠道代谢产物与肠道菌群结构特征，探讨清血消脂片改善肠道菌群结构及胆碱代谢紊乱与抗动脉粥样硬化作用的相关性，并从泡沫细胞形成和胆固醇摄取及逆向转运入手，探讨清血消脂片抗TMAO促动脉粥样硬化作用的机理，为化痰活血法中药防治肠道菌群失调相关心血管疾病的作用机制研究提供新的思路和方法。

动脉粥样硬化是人类死亡首要原因的心脑血管疾病的主要病理基础。近年的研究发现肠道菌群参与的胆碱代谢产物氧化三甲胺是一个重要的促动脉粥样硬化独立危险因素。本课题以添加胆碱的高脂饲料喂饲的小鼠动脉粥样硬化模型为实验对象，采用靶向和非靶向代谢组学，结合鉴定肠道菌群结构的16S rRNA 基因测序、宏基因组测序技术，并从胆固醇摄取及逆向转运的角度，揭示清血消脂片通过改善肠道菌群结构及胆碱-氧化三甲胺代谢紊乱抗动脉粥样硬化的作用机制，同时采用氧化三甲胺和氧化低密度脂蛋白诱导的小鼠Raw264.7建立泡沫细胞模型验证其作用机制。.研究结果表明，清血消脂片对添加胆碱的高脂饲料喂饲ApoE-/-小鼠动脉粥样硬化模型的动脉粥样硬化病理具有延缓作用，其作用包括对模型组的肠道菌群结构、胆碱及氧化三甲胺代谢紊乱具有明显的调节作用，使之向正常对照组回归。同时，清血消脂片可以减少巨噬细胞表面的清道夫受体CD36、SR-A1的mRNA及蛋白表达，增加调节胆固醇逆向转运相关受体PPARγ、LXRα、SR-B1、ABCA1和ABCG1的mRNA和蛋白的表达，从而降低泡沫细胞内胆固醇的含量。.本研究的结论为清血消脂片对添加胆碱的高脂饲料喂饲ApoE-/-小鼠动脉粥样硬化模型动脉粥样硬化病理具有延缓作用，其作用包括对模型组的肠道菌群结构、胆碱及氧化三甲胺代谢紊乱具有明显的调节作用，使之向正常对照组回归。其分子机制与减少胆固醇摄取和促进胆固醇逆转运，从而减少泡沫细胞形成有关。.本研究得出了“化痰活血中药清血消脂片通过调节肠道菌群结构，恢复胆碱-氧化三甲胺代谢异常，起到防治动脉粥样硬化的作用”的确切结论，为清血消脂片防治动脉粥样硬化的作用提供了科学依据，为院内制剂清血消脂片的临床应用提供了实验证据，为中医药防治与肠道菌群失调相关的心血管疾病和代谢性疾病的机理研究提供新的思路和方法。